US 12,270,799 B2
Gas sensors including microhotplates with resistive heaters, and related methods
Benjamin S. Rogers, Reno, NV (US); Christopher J. Dudley, Reno, NV (US); Dean A. Hopkins, Reno, NV (US); and Emil J. Geiger, Reno, NV (US)
Assigned to Nevada Nanotech Systems Inc., Sparks, NV (US)
Filed by Nevada Nanotech Systems Inc., Sparks, NV (US)
Filed on Jun. 18, 2021, as Appl. No. 17/304,355.
Application 17/304,355 is a continuation of application No. 15/959,807, filed on Apr. 23, 2018, granted, now 11,041,838.
Claims priority of provisional application 62/490,227, filed on Apr. 26, 2017.
Prior Publication US 2021/0311006 A1, Oct. 7, 2021
Int. Cl. G01N 33/00 (2006.01); G01N 25/18 (2006.01); G01N 25/22 (2006.01); G01N 25/48 (2006.01); G01N 27/12 (2006.01)
CPC G01N 33/0016 (2013.01) [G01N 25/18 (2013.01); G01N 25/22 (2013.01); G01N 25/48 (2013.01); G01N 27/125 (2013.01); G01N 33/0013 (2013.01); B01L 2300/0645 (2013.01); B01L 2300/12 (2013.01); B01L 2300/16 (2013.01); B01L 2300/1827 (2013.01); G01N 27/123 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A sensor, comprising:
a microhotplate comprising a membrane suspended over a substrate by a plurality of tethers, the membrane comprising a resistive heater exhibiting a varying width from a peripheral portion of the membrane to a center of the membrane;
a first conductive trace electrically connecting a first bond pad with a first portion of the resistive heater;
a second conductive trace electrically connecting a second bond pad with a second portion of the resistive heater;
a sense line in contact with a sense line bond pad and an end of the resistive heater, the sense line contacting the end of the resistive heater at a portion of the resistive heater between the first conductive trace and the second conductive trace;
interdigitated electrodes overlying the resistive heater;
electrode traces connecting the interdigitated electrodes to electrode bond pads; and
a sensing material in contact with the electrode traces, the electrode traces configured to measure an electrical resistance of the sensing material.